From 5ed679282b2ee0ccc536cf68926324566a8897db Mon Sep 17 00:00:00 2001 From: Evan Cheng Date: Wed, 7 Apr 2010 06:00:33 +0000 Subject: Add comments for missed opportunities. llvm-svn: 100610 --- llvm/lib/CodeGen/MachineLICM.cpp | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'llvm/lib/CodeGen/MachineLICM.cpp') diff --git a/llvm/lib/CodeGen/MachineLICM.cpp b/llvm/lib/CodeGen/MachineLICM.cpp index 72f7d4549c8..0edd44ba2e5 100644 --- a/llvm/lib/CodeGen/MachineLICM.cpp +++ b/llvm/lib/CodeGen/MachineLICM.cpp @@ -247,6 +247,8 @@ void MachineLICM::HoistRegionPostRA(MachineDomTreeNode *N) { if (!CurLoop->contains(BB)) continue; // Conservatively treat live-in's as an external def. + // FIXME: That means a reload that's reused into a fallthrough block + // will not be LICM'ed. for (MachineBasicBlock::const_livein_iterator I = BB->livein_begin(), E = BB->livein_end(); I != E; ++I) { unsigned Reg = *I; @@ -282,7 +284,8 @@ void MachineLICM::HoistRegionPostRA(MachineDomTreeNode *N) { } } - // FIXME: Only consider reloads for now. + // FIXME: Only consider reloads for now. We should be able to handle + // remat which does not have register operands. bool SkipCheck = false; int FI; if (SeenDef && !RuledOut) { -- cgit v1.2.3